Abstract
Purpose :
There is little information regarding the level of visual acuity children need to meet the typical demands of a classroom, yet such information is critical to developing appropriate visual screening guidelines as well as optimal classroom standards. This study sought to determine the actual visual requirements found in typical classrooms, in terms of logMAR demands and contrast sensitivity levels
Methods :
Careful measures of classroom dimensions with specific attention to viewing distances were made in several public and private school classrooms, at various grade levels, in New York City. Measurements were also made of typical text dimensions shown to students on smart boards and white boards. These measurements were used to calculate minimum and average logMAR demands at various seating locations within the classrooms. Estimations of letter vs. background contrast were made using photographic comparison to Pelli-Robson charts.
Results :
Three schools (8 classrooms total) were evaluated at several grade levels. Classroom dimensions varied significantly from school to school, ranging from 12ft x 14 ft to 23ft x 23ft. Based on the typical optotype sizes shown to students in each class, the seats closest to the front and center of the rooms required logMAR acuities of 0.71 to 1.13 (mean=0.85±0.12). Seats at the right and left of the front row required logMAR acuities of 0.49 to 0.99 (mean=0.67±0.15). Seats in the center of the back row required logMAR acuities of 0.1 to 0.52 (mean=0.32±0.14), while those at the right and left of the back row required logMAR acuities of 0.13 to 0.47 (mean=0.31±0.1). Contrast was high for black markers on white boards (CS=0.00), but varied from 0.15 to 0.60 on smart boards. Optotype dimensions did not vary with grade level (p=0.5).
Conclusions :
Our data suggest that actual visual demands vary greatly from classroom to classroom across schools, and within a given classroom. Contrast levels also vary greatly, and were highest with black markers on a white board and lowest on smart boards in rooms with high levels of ambient room light. This data, combined with visual acuity data obtained from large scale pediatric vision assessments, can be used to help determine appropriate acuity thresholds for ophthalmic or optometric referral, as well as inform schools regarding optimization of visual content in the classroom.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.